January 1900, Volume 待分类 Issue 待分类


          Letter to the Editor
Efficient allelic replacement in rice by gene editing: a case study of the NRT1.1B gene
Author: Jingying Li, Xin Zhang, Yongwei Sun, Jiahui Zhang, Wenming Du, Xiuping Guo, Shaoya Li, Yunde Zhao, Lanqin Xia
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: March 25, 2018
DOI: 10.1111/jipb.12650

Precise replacement of an existing allele in commercial cultivars with an elite allele is a major goal in crop breeding. A single nucleotide polymorphism in NRT1.1B gene between japonica and indica rice is responsible for the improved nitrogen use efficiency in indica rice. Herein, we precisely replaced the japonica NRT1.1B allele with the indica allele in just one generation using CRISPR/Cas9 gene editing technology. No additional selective pressure was needed to enrich the precise replacement events. This work demonstrates the feasibility of replacing any genes with elite alleles within one generation, greatly expanding our ability to improve agriculturally important traits.

Abstract (Browse 137)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
          Special Issue: Cell Signaling
Ethylene‐induced microtubule reorientation is essential for fast inhibition of root elongation in Arabidopsis
Author: Yichuan Wang, Yusi Ji, Ying Fu and Hongwei Guo
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: May 12, 2018
DOI: 10.1111/jipb.12666

Microtubule reorientation is a long‐standing observation that has been implicated in regulating the inhibitory effect of ethylene on axial elongation of plant cells. However, the signaling mechanism underlying ethylene‐induced microtubule reorientation has remained elusive. Here, we reveal, by live confocal imaging and kinetic root elongation assays, that the time courses of ethylene‐induced microtubule reorientation and root elongation inhibition are highly correlated, and that microtubule reorientation is required for the full responsiveness of root elongation to ethylene treatment. Our genetic analysis demonstrated that the effect of ethylene on microtubule orientation and root elongation is mainly transduced through the canonical linear ethylene signaling pathway. By employing pharmacological and genetic analyses, we demonstrate further that the TIR1/AFBs‐Aux/IAAs‐ARFs auxin signaling pathway, but not the ABP1‐ROP6‐RIC1 auxin signaling branch, is essential for ethylene‐induced microtubule reorientation and root elongation inhibition. Together, these findings offer evidence for the functional significance and elucidate the signaling mechanism for ethylene‐induced microtubule reorientation in fast root elongation inhibition in Arabidopsis.

Abstract (Browse 8)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
Receptor‐like protein kinases: Key regulators controlling root hair development in Arabidopsis thaliana
Author: Zhuoyun Wei and Jia Li
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: May 4, 2018
DOI: 10.1111/jipb.12663

Root hairs are tubular outgrowths specifically differentiated from epidermal cells in differentiation zone. The formation of root hairs greatly increases the surface area of a root and maximizes its ability to absorb water and inorganic nutrients essential for plant growth and development. Root hair development is strictly regulated by intracellular and intercellular signal communications. Cell surface‐localized receptor‐like protein kinases (RLKs) have been discovered as important components in these cellular processes. In this review, the functions of a number of key RLKs in regulating Arabidopsis root hair development are discussed, especially those involved in root epidermal cell fate determination and root hair tip growth.

Abstract (Browse 7)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
Insights into the regulation of CBF cold signaling in plants
Author: Jingyan Liu, Yiting Shi, and Shuhua Yang
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: April 18, 2018
DOI: 10.1111/jipb.12657

Cold temperatures, a major abiotic stress, threaten the growth and development of plants worldwide. To cope with this adverse environmental cue, plants from temperate climates have evolved an array of sophisticated mechanisms to acclimate to cold periods, increasing their ability to tolerate freezing stress. Over the last decade, significant progress has been made in determining the molecular mechanisms underpinning cold acclimation following the identification of several pivotal components, including candidates for cold sensors, protein kinases, and transcription factors. With these developments, we have a better understanding of the CBF‐dependent cold‐signaling pathway. In this review, we summarize recent progress made in elucidating the cold‐signaling pathways, especially the CBF‐dependent pathway, and describe the regulatory function of the crucial components of the plant cold signaling. We also discuss the unsolved questions that should be the focus of future work.

Abstract (Browse 20)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
Phosphatidic acid (PA) plays key roles regulating plant development and stress responses
Author: Hong-Yan Yao and Hong-Wei Xue
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: April 16, 2018
DOI: 10.1111/jipb.12655

Phospholipids, including phosphatidic acid (PA), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylserine (PS) and phosphoinositides, have emerged as an important class of cellular messenger molecules in various cellular and physiological processes, of which PA attracts much attentions of the researchers. In addition to its effect on stimulating the vesicle trafficking, many studies have demonstrated that PA plays a crucial role in various signaling pathways by binding target proteins and regulating their activity and subcellular localization. Here, we summarize the functional mechanisms and target proteins underlying PA‐mediated regulation of cellular signaling, development, hormonal responses, and stress responses in plants.

Abstract (Browse 29)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
ROS signaling and stomatal movement in plant responses to drought stress and pathogen attack
Author: Junsheng Qi, Chun-Peng Song, Baoshan Wang, Jianmin Zhou, Jaakko Kangasjärvi, Jian-Kang Zhu and Zhizhong Gong
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: April 16, 2018
DOI: 10.1111/jipb.12654

Stomata, the pores formed by a pair of guard cells, are the main gateways for water transpiration and photosynthetic CO2 exchange, as well as pathogen invasion in land plants. Guard cell movement is regulated by a combination of environmental factors including water status, light, CO2 levels and pathogen attack, as well as endogenous signals such as abscisic acid and apoplastic reactive oxygen species (ROS). Under abiotic and biotic stress conditions, extracellular ROS are mainly produced by plasma membrane‐localized NADPH oxidases, whereas intracellular ROS are produced in multiple organelles. These ROS form a sophisticated cellular signaling network, with the accumulation of apoplastic ROS an early hallmark of stomatal movement. Here, we review recent progress in understanding the molecular mechanisms of the ROS signaling network, primarily during drought stress and pathogen attack. We summarize the roles of apoplastic ROS in regulating stomatal movement, ABA and CO2 signaling, and immunity responses. Finally, we discuss ROS accumulation and communication between organelles and cells. This information provides a conceptual framework for understanding how ROS signaling is integrated with various signaling pathways during plant responses to abiotic and biotic stress stimuli.

Abstract (Browse 37)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
          Invited Expert Review
Expanding roles for pectins in plant development
Author: Adam M. Saffer
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: May 4, 2018
DOI: 10.1111/jipb.12662

Pectins are complex cell wall polysaccharides important for many aspects of plant development. Recent studies have discovered extensive physical interactions between pectins and other cell wall components, implicating pectins in new molecular functions. Pectins are often localized in spatially restricted patterns, and some of these non‐uniform pectin distributions contribute to multiple aspects of plant development, including the morphogenesis of cells and organs. Furthermore, a growing number of mutants affecting cell wall composition have begun to reveal the distinct contributions of different pectins to plant development. This review discusses the interactions of pectins with other cell wall components, the functions of pectins in controlling cellular morphology, and how non‐uniform pectin composition can be an important determinant of developmental processes.

Abstract (Browse 9)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
          Molecular Physiology
Arabidopsis VQ10 interacts with WRKY8 to modulate basal defense against Botrytis cinerea
Author: Junqiu Chen, Houping Wang, Yang Li, Jinjing Pan, Yanru Hu and Diqiu Yu
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: May 4, 2018
DOI: 10.1111/jipb.12664

Recent studies in Arabidopsis have revealed that some VQ motif‐containing proteins physically interact with WRKY transcription factors; however, their specific biological functions are still poorly understood. In this study, we confirmed the interaction between VQ10 and WRKY8, and found that VQ10 and WRKY8 formed a complex in the plant cell nucleus. Yeast two‐hybrid analysis showed that the middle region of WRKY8 and the VQ motif of VQ10 are critical for their interaction, and that their interaction promotes the DNA‐binding activity of WRKY8. Further investigation revealed that the VQ10 protein was exclusively localized in the nucleus, and VQ10 was predominantly expressed in siliques. VQ10 expression was strongly responsive to the necrotrophic fungal pathogen Botrytis cinerea and defense‐related hormones. Phenotypic analysis showed that disruption of VQ10 increased mutant plants susceptibility to the fungal pathogen B. cinerea, whereas constitutively‐expressing of VQ10 enhanced transgenic plants resistance to B. cinerea. Consistent with this, expression of the defense‐related PLANT DEFENSIN1.2 (PDF1.2) gene was decreased in vq10 mutant plants after B. cinerea infection but increased in VQ10‐overexpressing transgenic plants. Taken together, our findings provide evidence that VQ10 physically interacts with WRKY8 and positively regulates plant basal resistance against the necrotrophic fungal pathogen B. cinerea.

Abstract (Browse 7)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
Two soybean bHLH factors regulate response to iron deficiency
Author: Lin Li, Wenwen Gao, Qi Peng, Bin Zhou, Qihui Kong, Yinghui Ying, Huixia Shou
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: March 25, 2018
DOI: 10.1111/jipb.12651

Iron is an indispensable micronutrient for plant growth and development. Limited bioavailability of Fe in the soil leads to iron deficiency chlorosis in plants and yield loss. In this study, two soybean basic helix‐loop‐helix transcription factors, GmbHLH57 and GmbHLH300, were identified in response to Fe‐deficiency. Both transcription factors are expressed in roots and nodules, and are induced by Fe deficiency; these patterns were confirmed in transgenic hairy roots expressing constructs of the endogenous promoters fused to a GUS reporter gene. Bimolecular fluorescence complementation, yeast two‐hybrid and coimmunoprecipitation (co‐IP) assays indicted a physical interaction between GmbHLH57 and GmbHLH300. Studies on transgenic soybeans overexpressing GmbHLH57 and GmbHLH300 revealed that overexpression of each transcription factor, alone, result in a change of the responses to Fe deficiency, whereas overexpression of both transcription factors up‐regulated the downstream Fe uptake genes and increased the Fe content in these transgenic plants. Compared to wild type, these double overexpression transgenic plants were more tolerant to Fe deficiency. Taken together, our findings establish that GmbHLH57 and GmbHLH300 are important transcription factors involved in Fe homeostasis in soybean.

Abstract (Browse 32)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
The Arabidopsis catalase triple mutant reveals important roles of catalases and peroxisome derived signaling in plant development
Author: Tong Su, Pingping Wang, Huijuan Li, Yiwu Zhao, Yao Lu, Peng Dai, Tianqi Ren, Xiaofeng Wang, Xuezhi Li, Qun Shao, Dazhong Zhao, Yanxiu Zhao and Changle Ma
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: March 25, 2018
DOI: 10.1111/jipb.12649

Hydrogen peroxide (H2O2) is generated in many metabolic processes. As a signaling molecule, H2O2 plays important roles in plant growth and development, as well as environmental stress response. In Arabidopsis, there are three catalase genes, CAT1, CAT2, and CAT3. The encoded catalases are predominately peroxisomal proteins and are critical for scavenging H2O2. Since CAT1 and CAT3 are linked on chromosome 1, it has been almost impossible to generate cat1/3 and cat1/2/3 mutants by traditional genetic tools. In this study, we constructed cat1/3 double mutants and cat1/2/3 triple mutants by CRISPR/Cas9 to investigate the role of catalases. The cat1/2/3 triple mutants displayed severe redox disturbance and growth defects under physiological conditions compared with wild‐type and the cat2/3 double mutants. Transcriptome analysis showed a more profound transcriptional response in the cat1/2/3 triple mutants compared to the cat2/3mutants. These differentially expressed genes are involved in plant growth regulation as well as abiotic and biotic stress responses. In addition, expression of OXI1(OXIDATIVE SIGNAL INDUCIBLE 1) and several MAPK cascade genes were changed dramatically in the catalase triple mutant, suggesting that H2O2 produced in peroxisomes could serve as a peroxisomal retrograde signal.

Abstract (Browse 74)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
          Functional Omics and Systems Biology
Characterization of maize leaf Pyruvate Orthophosphate Dikinase using high throughput sequencing
Author: Yuling Zhang, Rita Giuliani, Youjun Zhang, Yang Zhang, Wagner Luiz Araujo, Baichen Wang, Peng Liu, Qi Sun, Asaph Cousins, Gerald Edwards, Alisdair Fernie, and Thomas P. Brutnell, Pinghua Li
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: April 17, 2018
DOI: 10.1111/jipb.12656

In C4 photosynthesis, pyruvate orthophosphate dikinase (PPDK) catalyzes the regeneration of phosphoenolpyruvate in the carbon shuttle pathway. Although the biochemical function of PPDK in maize is well characterized, a genetic analysis of PPDK has not been reported. In this study, we utilize the maize transposable elements Mutator and Ds to generate multiple mutant alleles of PPDK. Loss‐of‐function mutants are seedling lethal even when plants were grown under 2% CO2, and they show very low capacity for CO2 assimilation indicating C4 photosynthesis is essential in maize. Using RNA‐seq and GC‐MS technologies, we examined the transcriptional and metabolic responses to a deficiency in PPDK activity. These results indicate loss of PPDK results in down‐regulation of gene expression of enzymes of the C4 cycle, the Calvin cycle, and components of photochemistry. Furthermore, the loss of PPDK did not change Kranz anatomy, indicating that this metabolic defect in the C4 cycle did not impinge on the morphological differentiation of C4 characters. However, sugar metabolism and nitrogen utilization were altered in the mutants. An interaction between light intensity and genotype was also detected from transcriptome profiling, suggesting altered transcriptional and metabolic responses to environmental and endogenous signals in the PPDK mutants.

Abstract (Browse 22)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
Transcriptional and temporal response of Populus stems to gravi-stimulation
Author: Matthew Zinkgraf, Suzanne Gerttula, Shutang Zhao, Vladimir Filkov and AndrewLi Groover
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: February 26, 2018
DOI: 10.1111/jipb.12645

Plants modify development in response to external stimuli, to produce new growth that is appropriate for environmental conditions. For example, gravi-stimulation of leaning branches in angiosperm trees results in modifications of wood development, to produce tension wood that pulls leaning stems upright. Here, we use gravi-stimulation and tension wood response to dissect the temporal changes in gene expression underlying wood formation in Populus stems. Using time-series analysis of 7 time points over a 14-day experiment, we identified 8919 genes that were differentially expressed between tension wood (upper) and opposite wood (lower) sides of leaning stems. Clustering of differentially expressed genes showed four major transcriptional responses, including gene clusters whose transcript levels were associated with two types of tissue-specific impulse responses that peaked at about 24 – 48 hours, and gene clusters with sustained changes in transcript levels that persisted until the end of the 14-day experiment. Functional enrichment analysis of those clusters suggests they reflect temporal changes in pathways associated with hormone regulation, protein localization, cell wall biosynthesis and epigenetic processes. Time-series analysis of gene expression is an underutilized approach for dissecting complex developmental responses in plants, and can reveal gene clusters and mechanisms influencing development.

Abstract (Browse 78)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
          Plant Reproduction Biology
Arabidopsis thaliana NOP10 is required for gametophyte formation
Author: Lin-Xiao Li, Hong-Ze Liao, Li-Xi Jiang, Qing Tan, De Ye and Xue-Qin Zhang
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: March 26, 2018
DOI: 10.1111/jipb.12652

The female gametophyte is crucial for sexual reproduction of higher plants, yet little is known about the molecular mechanisms underlying its development. Here, we report that Arabidopsis thaliana NOP10 (AtNOP10) is required for female gametophyte formation. AtNOP10 was expressed predominantly in the seedling and reproductive tissues, including anthers, pollen grains, and ovules. Mutations in AtNOP10 interrupted mitosis of the functional megaspore during early development and prevented polar nuclear fusion in the embryo sacs. AtNOP10 shares a high level of amino acid sequence similarity with Saccharomyces cerevisiae (yeast) NOP10 (ScNOP10), an important component of the H/ACA small nucleolar ribonucleoprotein particles (H/ACA snoRNPs) implicated in 18S rRNA synthesis and rRNA pseudouridylation. Heterologous expression of ScNOP10 complemented the mutant phenotype of Atnop10. Thus, AtNOP10 influences functional megaspore mitosis and polar nuclear fusion during gametophyte formation in Arabidopsis.

Abstract (Browse 49)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
          Plant-abiotic Interactions
bHLH104 confers tolerance to cadmium stress in Arabidopsis thaliana
Author: Xiani Yao, Yuerong Cai, Diqiu Yu, Gang Liang
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: April 18, 2018
DOI: 10.1111/jipb.12658

Cd is a non‐essential heavy metal that is toxic to both plants and animals. Here, we reveal that the transcription factor bHLH104 positively regulates Cd tolerance in Arabidopsis thaliana. We found that Fe deficiency‐responsive genes were induced by Cd treatment, and that their upregulation was suppressed in bhlh104 loss‐of‐function mutants but enhanced upon overexpression of bHLH104. Correspondingly, the bhlh104 mutants displayed sensitivity to Cd stress, whereas plants overexpressing bHLH104 exhibited enhanced Cd tolerance. Further analysis suggested that bHLH104 positively regulates four heavy metal detoxification‐associated genes, IREG2, MTP3, HMA3 and NAS4, which play roles in Cd sequestration and tolerance. The bHLH104 overexpression plants accumulated high levels of Cd in the root but low levels of Cd in the shoot, which might contribute to the Cd tolerance in those lines. The present study thus points to bHLH104 as a potentially useful tool for genetic engineering of plants with enhanced Cd tolerance.

Abstract (Browse 21)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
Hormone modulation of legume‐rhizobial symbiosis
Author: Huan Liu, Chi Zhang, Jun Yang, Nan Yu and Ertao Wang
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: March 26, 2018
DOI: 10.1111/jipb.12653

Leguminous plants can establish symbiotic associations with diazotropic rhizobia to form nitrogen‐fixating nodules, which are classified as determinate or indeterminate based on the persistence of nodule meristem. The formation of nitrogen‐fixing nodules requires coordinating rhizobial infection and root nodule organogenesis. The formation of infection thread and the extent of nodule formation are largely under plant control but vary with environmental conditions and the physiological state of the host plants. Many achievements in these two areas have progressed in recent decades. Phytohormone signaling pathways have gradually emerged as important regulators of root nodule symbiosis. Cytokinin, strigolactones (SLs) and local accumulation of auxin can promote nodule development. Ethylene, jasmonic acid (JA), abscisic acid (ABA) and gibberellic acid (GA) all negatively regulate infection thread formation and nodule development. However, salicylic acid (SA) and brassinosteroids (BRs) have different effects on the formation of these two nodule types. Some peptide hormones are also involved in nodulation. This review summarizes recent findings on the roles of these plant hormones in legume‐rhizobial symbiosis and proposes that DELLA proteins may function as a node to integrate plant hormones to regulate nodulation.

Abstract (Browse 60)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
          Cell and Developmental Biology
Non‐dormant Axillary Bud 1 regulates axillary bud outgrowth in sorghum
Author: Jun Chen, Limin Zhang, Mengjiao Zhu, Lijie Han, Ya Lv, Yishan Liu, Pan Li, Haichun Jing and Hongwei Cai
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: May 8, 2018
DOI: 10.1111/jipb.12665

Tillering contributes to grain yield and plant architecture and therefore is an agronomically important trait in sorghum (Sorghum bicolor). Here, we identified and functionally characterized a mutant of the Non‐dormant Axillary Bud 1 (NAB1) gene from an ethyl methanesulfonate‐mutagenized sorghum population. The nab1 mutants have increased tillering and reduced plant height. Map‐based cloning revealed that NAB1 encodes a carotenoid‐cleavage dioxygenase 7 (CCD7) orthologous to rice (Oryza sativa) HIGH‐TILLERING DWARF1/DWARF17 and Arabidopsis thaliana MORE AXILLARY BRANCHING 3. NAB1 is primarily expressed in axillary nodes and tiller bases and NAB1 localizes to chloroplasts. The nab1 mutation causes outgrowth of basal axillary buds; removing these non‐dormant basal axillary buds restored the wild‐type phenotype. The tillering of nab1 plants was completely suppressed by exogenous application of the synthetic strigolactone analog GR24. Moreover, the nab1 plants had no detectable strigolactones and displayed stronger polar auxin transport than wild‐type plants. Finally, RNA‐seq showed that the expression of genes involved in multiple processes, including auxin‐related genes, was significantly altered in nab1. These results suggest that NAB1 functions in strigolactone biosynthesis and the regulation of shoot branching via an interaction with auxin transport.

Abstract (Browse 13)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
Plant glycosylphosphatidylinositol (GPI) anchored proteins at the plasma membrane‐cell wall nexus
Author: Trevor H. Yeats, Antony Bacic and Kim L. Johnson
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: April 18, 2018
DOI: 10.1111/jipb.12659

Approximately 1% of plant proteins are predicted to be post‐translationally modified with a glycosylphosphatidylinositol (GPI) anchor that tethers the polypeptide to the outer leaflet of the plasma membrane. While the synthesis and structure of GPI anchors is largely conserved across eukaryotes, the repertoire of functional domains present in the GPI‐anchored proteome has diverged substantially. In plants, this includes a large fraction of the GPI‐anchored proteome being further modified with plant‐specific arabinogalactan (AG) O‐glycans. The importance of the GPI‐anchored proteome to plant development is underscored by the fact that GPI biosynthetic null mutants exhibit embryo lethality. Mutations in genes encoding specific GPI‐anchored proteins (GAPs) further supports their contribution to diverse biological processes occurring at the interface of the plasma membrane and cell wall, including signaling, cell wall metabolism, cell wall polymer cross‐linking, and plasmodesmatal transport. Here, we review the literature concerning plant GPI‐anchored proteins in the context of their potential to act as molecular hubs that mediate interactions between the plasma membrane and the cell wall and their potential to transduce the signal into the protoplast and thereby activate signal transduction pathways.

Abstract (Browse 22)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
Plant G proteins interact with ER luminal protein receptors to regulate ER retrieval
Author: Shanshan Wang, Ke Xie, Guoyong Xu, Huarui Zhou, Qiang Guo, Jingyi Wu, Zengwei Liao, Na Liu, Yan Wang and Yule Liu
Journal of Integrative Plant Biology 1900 待分类(待分类)
Published Online: March 23, 2018
DOI: 10.1111/jipb.12648

Maintaining endoplasmic reticulum (ER) homeostasis is essential for the production of biomolecules. ER retrieval, i.e., the retrograde transport of compounds from the Golgi to the ER, is one of the pathways that ensures ER homeostasis. However, the mechanisms underlying the regulation of ER retrieval in plants remain largely unknown. Plant ERD2‐like proteins (ERD2s) were recently suggested to function as ER luminal protein receptors that mediate ER retrieval. Here, we demonstrate that heterotrimeric G protein signaling is involved in ERD2‐mediated ER retrieval. We show that ERD2s interact with the heterotrimeric G protein Gα and Gγ subunits at the Golgi. Silencing of , , or increased the retention of ER luminal proteins. Furthermore, overexpression of Gα, Gβ, or Gγ caused ER luminal proteins to escape from the ER, as did the co‐silencing of ERD2a and ERD2b. These results suggest that G proteins interact with ER luminal protein receptors to regulate ER retrieval.

Abstract (Browse 34)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
          Plant-pathogen Interactions
Leaf stage‐associated resistance is correlated with phytohormones in a pathosystem‐dependent manner
Author: You-Ping Xu, Lin-Hui Lv, Ya-Jing Xu, Juan Yang, Jia-Yi Cao and Xin-Zhong Cai
Journal of Integrative Plant Biology 1900 待分类(待分类)
DOI: 10.1111/jipb.12661

It has been reported in several pathosystems that disease resistance can vary in leaves at different stages. However, how general this leaf stage‐associated resistance is, and the molecular mechanism(s) underlying it, remain largely unknown. Here, we investigated the effect of leaf stage on basal resistance, effector‐triggered immunity (ETI) and nonhost resistance, using eight pathosystems involving the hosts Arabidopsis thaliana, Nicotiana tabacum, and N. benthamiana and the pathogens Sclerotinia sclerotiorum, Pseudomonas syringae pv. tabaci, P. syringae pv tomato DC3000, and Xanthomonas oryzae pv. oryzae (Xoo). We found evidence that leaf stage‐associated resistance exists ubiquitously in plants, but with varying intensity at different stages in diverse pathosystems. Microarray expression profiling assays demonstrated that hundreds of genes involved in defense responses, phytohormone biosynthesis and signaling, and calcium signaling, were differentially expressed between leaves at different stages. The Arabidopsis mutants sid1, sid2‐3, ein2, jar1‐1, aba1 and aao3 lost leaf stage‐associated resistance to S. sclerotiorum, and the mutants aba1 and sid2‐3 were affected in leaf stage‐associated RPS2/AvrRpt2+‐conferred ETI, while only the mutant sid2‐3 influenced leaf stage‐associated nonhost resistance to Xoo. Our results reveal that the phytohormones salicylic acid, ethylene, jasmonic acid and abscisic acid likely play an essential but pathosystem‐dependent role in leaf stage‐associated resistance.

Abstract (Browse 11)  |  References  |  Full Text HTML  |  Full Text PDF  |  Cited By       
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